The net result? Johnson, who finished third, widened his lead over the struggling Kenseth, who ran 23rd, and took a giant step toward his sixth series championship.

Johnson expanded his advantage in the Chase for the NASCAR Sprint Cup standings from seven to 28 points over Kenseth entering next Sunday's season finale at Homestead-Miami Speedway. Johnson can clinch the title with a finish of 23rd or better, 24th if he leads one lap and 25th if he leads the most laps.

By winning and leading the most laps on Sunday, Harvick, third in the standings, narrowed his deficit to Johnson from 40 to 34 points and is still within range of the title, should Johnson have issues at Homestead.

The victory was Harvick's fourth at the one-mile track and the 23rd of his career. He led 70 of the 312 laps to clinch the 200th win for the Childress organization in NASCAR's three national series. It came as a sudden surprise, as Edwards slowed on the final lap.

"Well, I think we were all pushing it on gas there to try to just put enough in it to get to the end, so that we could gain all the track position we could under green," Harvick said of his final pit stop on Lap 267. "I saw him slowing with about maybe a lap and a half, two laps to go. (Team owner) Richard (Childress) came across the radio and said he was slowing down. I'm like 'Dang, we might still be in this thing.' "

Kasey Kahne ran second, followed by Johnson, Dale Earnhardt Jr. and Kurt Busch. Edwards, who ran out of gas while leading on the final lap, finished 21st. Edwards slid up into Johnson's car on Lap 163, dropping Johnson back to 24th after Harvick took them three-wide entering Turn 1. Johnson made a spectacular save and spent the rest of the race working his way toward the front.

Johnson started from the pole but, thanks in part to Joey Logano's dive to the inside, failed to launch at the green flag, a tendency that would plague him all afternoon. Trouble on restarts may have kept the five-time champion from winning the race, but they didn't prevent him from recovering nicely when the incident with Edwards left him back in the pack.

"At two different points, as I saved it, the car pointed back at the fence, and I thought I was going to hit it," Johnson said. "Thankful that that didn't happen, clearly. [It] certainly worried me, and then we were mired in traffic after that, and I didn't know what that was going to mean for us."

Kenseth, on the other hand, could make little progress with a balky car whose handling deteriorated throughout the race, despite the best efforts of his crew to correct the problem. Worse, a miscommunication on a 164th-lap stop under caution resulted in a dramatically sluggish trip to pit lane that lasted nearly 26 seconds and dropped Kenseth from seventh to 29th in the running order.

"Obviously, it didn't drive good or we would have been up there with the front group," Kenseth said. "I just did all I could with it, which wasn't much."

Though Johnson enjoys a hefty advantage approaching the season finale, he was far from ready to lay claim to the title.

"Yeah, everybody is so eager to predict the champion, but you've got to play the game," said Johnson, who has finished 32nd and 36th in his last two races at Homestead. "You've got to run the race, and stuff happens. There’s so many variables in one of our races -- I think more variables than any pro sport out there.

"We have all 43 teams playing, driving, racing, all the mechanical components on the race car, pit stops, other issues on other cars that can take you out … tires. There's a lot of variables, so we don't take any of these weekends lightly. Even with a nice points lead I'm not going to take any week any differently. There's still a lot of pressure to get the job done, and it's no lay‑up at all."

Johnson, Kenseth and Harvick are the only three drivers with a chance to win the championship. Kyle Busch (fourth in the standings) and Earnhardt (fifth) were among those eliminated at Phoenix.

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